Research And Development Of Simulation System About Laser Beam Propagation Through Atmosphere Based On HLA

The system simulation technology applied in more and more fields, in the field of photoelectric countermeasure, the simulation of laser atmospheric propagation is a very important part. A methodology of simulation of laser beams propagation through atmosphere is put forward, including modeling and development of simulation program.High Energy Laser (HEL) beams propagating through the earth's atmosphere are influenced by a wide variety of effects which, in general, reduce the beam irradiance (or, power concentration) at the target. The most important atmospheric propagation effects for continuous-wave (cw) HEL systems include linear absorption and scattering due to molecular and aerosol, turbulence, and nonlinear thermal blooming. Theories of these effects introduced in the first instance, the method of simulation of HEL beams propagation through atmosphere is build in virtue of the detailed analysis of model and arithmetic. At the same time, with a view to characteristics of HEL atmospheric propagation and speed of simulation demanded, problems how to calculate atmospheric transmittance and to select parameters are discussed.High Level Architecture (HLA) is the main direction of development of distributive simulations for the future. In the process of practising of simulation, for one thing, the program function as a federate based on HLA is developed by using multi-thread in Visual C++ (VC) 6.0 and HLA simulation technologies. On the other hand, HLA-based simulation system of laser beam propagation through atmosphere is completed by means of the combination of entitative and interactive model, static and dynamic parameters together. In particular, with the way how to input and output files analyzed, MODTRAN is integrated into simulation program based on VC6.0. In addition, the program is designed with manual and automatic mode, and many accessory functions are realized by taking full advantage of powerful VC6.0 and C/C++ language, such as saving/opening database files, printing/previewing report forms, displaying/analyzing curves of data. Furthermore, the simulation system can be finally as one of federates of HLA-based photoelectric countermeasure federation.